1. Field of the Invention
The present invention relates generally to a eye surgery, and more particularly to surgical instrumentation and to a method for supporting a cannula relative to an eye in which the cannula can be actuated to irrigate the eye.
2. Description of the Prior Art
Traditionally, retinal surgeons relied on standard operating microscopes in conjunction with surgical contact lenses to view the interior of the eye. During use, the surgical contact lenses are held in place on the corneal surface of the eye. However, even though the surgical contact lenses provided a clear view of the interior of the eye, such lenses afforded only a limited field of view. Moreover, given that the surgical contact lenses must be held in place on the corneal surface, retinal surgeons were limited in their ability to manipulate the eye.
Binocular indirect opthalmo microscopes (BIOMs) with wide-angle viewing systems are commonly employed by retinal surgeons during posterior segment eye surgery. BIOMs with wide-angle viewing systems offer superior functionality over standard operating microscopes used in conjunction with surgical contact lenses. BIOMs with wide-angle viewing systems allow for a greater field of view and increased surgical mobility. Rather than using surgical contact lenses, BIOMs with wide-angle viewing systems employ non-contact lens assemblies to view the interior of the eye. The non-contact lens assemblies include non-contact lenses positioned along the focal axes of the BIOMs. When focusing the BIOMs on the interior of the eye, the retinal surgeon adjusts and positions the non-contact lenses along the focal axes using positioning mechanisms.
To properly focus the BIOMs, the non-contact lenses must be positioned in close proximity to the eye. For example, the non-contact lenses are often positioned less than one inch from the corneal surface. During surgery, such close proximity to the corneal surface creates difficulties in keeping the corneal surface wet and consequently clear.
Typically, surgical assistants assist the retinal surgeons during surgery, and are charged with irrigating the eye. In doing so, the surgical assistants manually position and actuate a cannula to supply fluid to the eye. The close proximity of the non-contact lens to the eye can lead to unintentional wetting with fluid from the cannula when attempting to the irrigate the eye. Such unintentional wetting can delay the surgery until the non-contact lenses are cleaned or the non-contact lens assemblies are replaced. Moreover, because the surgical assistants must usually look up from oculars to manually position and actuate the cannula, there is also danger that manipulation of the cannula will deleteriously interfere with the surgery.
Therefore, there exists a need for surgical instrumentation and a method for supporting a cannula relative to an eye in which the cannula can be actuated to irrigate the eye, while inhibiting unintentional wetting of the non-contact lens and deleterious interference with the surgery.